ABB ACS880 Series Firmware Manual page 15

Term/abbre- Definition
viation
PLC Programmable logic controller
Power unit Contains the power electronics and power connections of the drive (or inverter
module). The drive control unit is connected to the power unit.
PTC Positive temperature coefficient
PU See
RDCO-0x Optional DDCS communication module
RFG Ramp function generator.
RO Relay output; interface for a digital output signal. Implemented with a relay.
SSI Synchronous serial interface
STO Safe torque off
Supply unit In large drives (> 500 kW approx.), the part of the drive that converts AC to
DC. Consists of one or more supply modules and their auxiliary components.
An IGBT supply unit (ISU) is also capable of feeding regenerative energy back
into the supply network.
TTL Transistor-transistor logic
UPS Uninterruptible power supply; power supply equipment with battery to
maintain output voltage during power failure
ZCU Type of control unit used in ACS880 drives (primarily in drive modules, or
inverter/supply units consisting of a single power module). Consists of an I/O
board built into a plastic housing.
Depending on the type of hardware, the control unit may be integrated into or
fitted onto the drive/inverter module, or installed separately.
power unit.
Introduction to the manual 15